[justfx]

I picked up a couple of older Electro-craft servos today and am having a hard time finding specs online for them. They are Model E19-3 part number 0644-06-011. I'm hoping someone has an old catalog page they could post with the info. Thanks.

[jalessi]

Checkout page number nine, you will be happy.


http://www.electrocraft.com/files/el...aft_legacy.pdf


Jeff...

[justfx]

Thanks for the quick reply Jeff. I think while similar (in the same motor lineage) the 0640 series is older than the G640 series and pre-dates any info I can find on the web. Anyone else?

[jalessi]

The motor you have is about 1/2 horsepower.

Jeff...

[Al_The_Man]

This may help.
Al.

[justfx]

Thanks Al! You are the man! Just what I was looking for.

[jonshepley]

Hi, I have a similar part number, I dont suppose you still have the catalog do you? The motor is as follows:

Electro-Craft Ltd
Servo Motor E19-3
Part No 0644-31-001

Any info on this part would be appreciated, I'm struggling to find anything at the moment.

Thanks,

Jon

[Al_The_Man]

I have for the basic 0644.
12.0 LB-In continuous stall torque
60.0 LB-In Peak
Max rpm 1850
Kt (Lb-in/amp) 2.74
Max Pulse current 22.A
Max Terminal Voltage 60v
Al.

[jonshepley]

Great, thanks for your fast reply in this

[jonshepley]

Hi Al_The_Man,

Thanks again for that info, I'm just playing with the motor now, its part of a big Radamec Pan/Tilt head which i want to hook up to a controller. The motors have 4 wires, Red and Black (These are definatly the motor winding, its about 10Ohms and spins up the motor when energised) The other 2 wires are Blue and White, they have a DC resistance or around 100Ohms, I presume these are connected to the encoder? Can't seem to find any examples of 4 wire motors like this online. The thing that is throwing me is that there is a seporate encoder geared onto each drive shaft it's made by Muirhead-Vactric Components and has 5 terminals (R1, R2, S1, S2 and S3) it says Synchro control transmitter. It also says"PRI - R1-R2 115V" "SEC - S1-S2-S3 90V" Part number 5990-99-639-8901. I'm not farmilular with these devices but i've been reading about them on wiki. I don't suppose you know of any off the shelf controllers what would be suitable for this application do you?

Thanks so much for your help.

Jon

[Al_The_Man]

The blue and white sound like the tach, if you have another pair of smaller brushes, then it is.
The position detector is a resolver OWKA Synchro Transmitter, used in place of an encoder, there are some convertors out there, but usually the optimum way is to remove it and fit a quadrature encoder.
Al.

[jonshepley]

Hi Al,

That makes sense, there are what look like 4 replaceable bushes on the main body of the motor (they look abit like replaceable fuses from the outside) then there are 2 just above 180 degrees apart. The slightly strange thing is that the blue and white wires are both the same gauge as the power cables for the motor, is this normal?

Thanks, Jon

[Al_The_Man]

The two at 180° will be the tach, you can remove the caps and check continuity to the Blue and white. Also the brushes will be much smaller than the 4 main brushes.
If using modern drives, the tach brushes can be removed as modern drives rarley use the velocity mode now.
Al.